title: Tumor inhibitory T cell immunity may be largely a transplantation artifact not necessarily dependent upon a lack of Tregs.
abstract: There exists a very large literature suggesting that T cells come in a variety of species and that without the action of Tregs tumors would seldom survive inhibition by T cell effectors. We believe that much of the evidence supporting the role of Tregs in cancer is compatible with a perhaps simpler hypothesis based upon the demonstration that that small quantities of effector T cells tend to stimulate tumors while larger quantities of seemingly the same cells are inhibitory (an hormesis-like effect). This possibility seems to destroy much of the need to postulate a role for T cell suppressors (Tregs) in cancer, but the exposure of effector T cells to antigen may convert them into Tregs (Tregs do exist). Furthermore, many other data suggest the possibility that immune inhibition of cancer could be a laboratory artifact seldom if ever seen in unmodified nature.
authors.affiliation: Department of Pathology, University of Washington School of Medicine, Seattle 98118, USA. prehn@u.washington.edu
authors.forename: Richmond T
authors.initials: RT
authors.lastname: Prehn
authors.forename: Liisa M
authors.initials: LM
authors.lastname: Prehn
mesh_terms: D016477:Artifacts; D049109:Cell Proliferation; D006801:Humans; D007109:Immunity / Q000276:immunology*; D007114:Immunization; D018448:Models, Immunological; D009369:Neoplasms / Q000276:immunology* / Q000473:pathology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*